Pressure regulator valves are used in a variety of different applications to regulate the flow rate and pressure of a pressurized fluid. Many pressure regulator valves include a valve with one or more lands disposed within a valve bore. The valve may slide within the valve bore in response to changing system conditions to thereby move the one or more lands relative to openings in the valve body and thereby control a fluid pressure and flow rate. The position of the valve within the valve bore may be controlled, in part, by input control fluids that impinge upon a surface of the lands of the valve. The force the input control fluids impart on the valve will vary with the area of the surface the fluid acts on such that, for a given input control fluid pressure, the position of the valve within the valve bore will vary depending on a surface area of the lands. Thus, the ratio of the input control fluid pressure to the regulated pressure can vary depending on the surface area of the lands. The size of the valves and the size of the valve bore in a pressure regulator valve can therefore vary depending on the system pressure the pressure regulator valve is designed for. Some systems also include a boost assembly valve that is positioned adjacent to the pressure regulator valve, and that can influence the position of the pressure regulator valve, and thus, influence the regulated pressure.
A common application for pressure regulator valves and boost assembly valves is automobile automatic transmissions, where a valve assembly that includes a pressure regulator valve and a boost assembly valve is used to regulate the transmission main line pressure under varying operating conditions. In a typical transmission, the main line pressure is routed to other valves in the transmission, may be re-regulated for certain portions of the system, and is typically used to apply clutches, bands, accumulators, solenoids, the torque converter, and lubricate essential components of the system. Proper functioning of the valve assembly is therefore critical to the proper functioning of the transmission. Transmissions for larger vehicles generally require a higher main line pressure than transmissions for smaller vehicles. Also, transmissions for high performance vehicles can often require a higher main line pressure than more conventional vehicles of the same size. Thus, a separate valve assembly having a particular valve bore diameter and valve land diameters may need to be designed for each vehicle transmission according to the desired main line pressure. In addition, because of the constant movement of the valves within the valve body, the valve assembly often wears out and needs to be replaced. A manufacturer that sells replacement pressure regulator valves or boost valve assemblies, or kits for replacing valve components, generally must manufacture and sell a plurality of different valves or kits, each corresponding to a particular valve bore diameter and valve land diameter for a particular vehicle.